Electromechanical memory devices, such as hard disk drives (HDD), are increasingly yielding to solid state drives (SSD) and other memory devices in computing environments requiring faster speed, quieter noise, lower power, compact size and cheaper prices. Under various U.S. Federal and State government regulatory schemes, however, there exist a number of laws, rules, specifications, procedures, etc. that dictate standards for the secure destruction of data from memory regardless of type. (See, e.g., National Institute of Standards and Technology (NIST) Special Publication 800-88, Guidelines for Media Sanitization.) Not only must data be erased, it must be erased in a manner that masks previous storage states to prevent a hacker's later reconstruction of content. The procedures often call for significant numbers of erasures/overwriting to memory locations over the life of devices containing data. While electromechanical memory devices tend to durably withstand these commands over time, SSD, (E)EPROM and other flash memory devices do not fare as well. Artisans have noted significant degradation and failure in the latter after a few thousand erasure cycles. The problems range from “leaky” memory cells to failed bits to failed sectors or blocks.
Artisans have attempted to overcome these problems and prolong service lives of memory with various techniques that “level out” premature wear (known as “wear leveling”). Some of the techniques track erasure and re-write commands in devices in an attempt to disseminate commands evenly amongst all memory sectors or blocks to level out their wear. In other techniques, artisans reserve memory space that becomes used only upon the failure of non-reserve memory spaces. Checksums are often used to note the failures of blocks or sectors. Upon the failure of just a few sectors, the entire memory device often fails. Unfortunately, each of these requires sophisticated mapping and tracking of memory that complicates implementation.
What is needed is a simple, yet elegant solution to gain the inherent advantages of SSD, flash, (E)EPROM, etc. The need extends to affording the highest levels of secure destruction according to state and federal mandates, but without premature wear. Additional benefits and alternatives are also sought when devising solutions.